The provision of centralised charging functionality is likely to be a key issue in all-IP (Internet protocol) networks, such as mobile communications networks in which a packet switched cellular network provides access for mobile users to services provided by external IP networks.
Diameter is an IETF protocol that has been specifically designed for the Internet infrastructure. Diameter unifies authentication, authorization and accounting (AAA) transactions. The accounting related extension of the base Diameter protocol is likely to be used in networks which are all-IP (Internet Protocol) based for charging purposes.
An essential feature of the provision of charging functions in all-IP based networks is that on-line charging must be provided for, which may require for the information associated with an accounting session to be updated dynamically. However, the existing Diameter protocol does not specifically allow for on-line charging capability.
It is an object of the present invention to provide an improved technique for charging in IP networks, which addresses one or all of the above-stated problems.